Endoscopes, such as colonoscopes, that are currently being used, typically have multiple viewing elements, such as cameras, that correspondingly include Charge Coupled Device (CCD) or CMOS image sensors to generate video feeds. CCD as well as CMOS image sensors are fraught with problems, such as saturation and blooming, that affect both their quantitative and qualitative imaging characteristics. For example, if each individual pixel can be thought of as a well of electrons, then saturation refers to the condition where the well becomes filled. The amount of charge that can be accumulated in a single pixel is determined largely by its area. However, due to the nature of the potential well, which holds charge within a pixel, there is less probability of trapping an electron within a well that is approaching saturation. Therefore, as a well approaches its limit, the linear relationship between light intensity and signal degrades. As a result, the apparent responsivity of a saturated pixel drops.
At saturation, pixels lose their ability to accommodate additional charge. This additional charge then spreads into neighboring pixels, causing them to either report erroneous values or also saturate. This spread of charge to adjacent pixels is known as blooming and appears as a white streak or blob in the image. The occurrence of blooming, in video images generated by a multi-viewing elements endoscope, results in loss of details in portions of the video image and is a serious cause of concern for a physician performing an endoscopic procedure.
Accordingly, there is need in the art for processing the video feeds generated by a plurality of viewing elements of an endoscopic tip such that saturation is minimized and/or the occurrence of blooming is effectively controlled in the video feeds.